The present invention generally relates to a foot-operated control device for a parking brake of a vehicle, and more particularly to a control device which is manipulated solely by foot by the vehicle operator to release the parking brake being applied to the vehicle.
In the art of a foot-operated control device for a parking brake wherein a parking brake pedal is depressed by foot to apply the parking brake, the operation by the operator to release the applied parking brake has been conducted by hand. Such conventional control device suffers various problems such as: difficult manipulation for releasing the brake due to the operator's need for leaning forward while pulling a seat belt; generation of considerable sounds of impact of the brake pedal at the end of the quick return to its non-operated position upon releasing the brake; and difficult starting of a vehicle parked on a slope.
To overcome the above problems, there has been proposed a device as disclosed in JITSU-KAI-SHO 55-146363, publication of Japanese Utility Model application for public inspection, the disclosure of which is hereby incorporated by reference, wherein a parking brake is released by pivoting by foot a pedal pad pivotally connected to a parking brake pedal. To connect the pedal pad to a pawl member which is pivotally connected to the brake pedal and held in engagement with ratchet teeth by a first spring member, the disclosed device employs a linking mechanism which comprises an intermediate lever and a transmission rod which is connected at one end to the intermediate lever and at the other end to the pedal pad, so that a pivotal motion of the pedal pad in one direction by foot depression thereof is converted into a linear vertical motion of the transmission rod which in turn is changed into a pivotal motion of the intermediate lever which then causes a second spring member between the lever and the pawl member to be flexed, whereby the pawl member is biased by the second spring member in a direction opposite to the biasing direction of the first spring member, i.e., in the direction that causes the pawl member to disengage from the ratchet teeth. A pivotal movement of the brake pedal by applying a further depression onto the pedal pad in this condition will result in removal of an engagement force which has existed between the pawl member and the ratchet teeth, thereby permitting disengagement of the pawl member from the ratchet teeth.
However, the above foot-operated control device known in the art which uses the transmission rod and the intermediate lever is not satisfactory in view of its complicated linking mechanism and the consequent increase in the cost of manufacture.